State Key Laboratory of Marine Food Processing and Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China.
Qingdao Key Laboratory of Food Biotechnology, Qingdao 266404, China.
J Agric Food Chem. 2024 May 1;72(17):9967-9973. doi: 10.1021/acs.jafc.4c00498. Epub 2024 Apr 19.
The use of convertible immobilized enzyme carriers is crucial for biphasic catalytic reactions conducted in Pickering emulsions. However, the intense mechanical forces during the conversion process lead to enzyme leakage, affecting the stability of the immobilized enzymes. In this study, a CO-responsive switchable Janus (CrSJ) nanoparticle (NP) was developed using silica NP, with one side featuring aldehyde groups and the other side adsorbing ,-dimethyldodecylamine. A switchable Pickering emulsion catalytic system for biphasic interface reactions was prepared by covalently immobilizing lipase onto the CrSJ NPs. The CO-responsive nature of the CrSJ NPs allowed for rapid conversion of the Pickering emulsion, and covalent immobilization substantially reduced lipase leakage while enhancing the stability of the immobilization during the conversion process. Impressively, after repeated transformations, the Pickering emulsion still maintains its original structure. Following 10 consecutive cycles of esterification and hydrolysis reactions, the immobilized enzyme's activity remains at 77.7 and 79.5% of its initial activity, respectively. The of the CrSJ catalytic system showed no significant change compared to the free enzyme, while its values were 1.2 and 1.6 times that of the free enzyme in esterification and hydrolysis reactions, respectively.
可转化固定化酶载体在 Pickering 乳液中进行两相催化反应中至关重要。然而，在转化过程中强烈的机械力会导致酶泄漏，从而影响固定化酶的稳定性。在本研究中，使用二氧化硅纳米粒子（NP）开发了一种 CO 响应型可切换的 Janus（CrSJ）纳米粒子（NP），其一侧具有醛基，另一侧吸附 - 二甲基十二烷基胺。通过将脂肪酶共价固定在 CrSJ NPs 上，制备了用于两相界面反应的可切换 Pickering 乳液催化体系。CrSJ NPs 的 CO 响应特性允许 Pickering 乳液快速转化，共价固定化在转化过程中大大减少了脂肪酶泄漏，同时提高了固定化的稳定性。令人印象深刻的是，经过多次反复转化，Pickering 乳液仍保持其原始结构。在连续进行 10 次酯化和水解反应后，固定化酶的活性分别保持在初始活性的 77.7%和 79.5%。与游离酶相比，CrSJ 催化体系的 没有明显变化，而其在酯化和水解反应中的 值分别是游离酶的 1.2 和 1.6 倍。
